Work handling apparatus for machine tools



May 22, 1956 w. R. MEYER ETAL 2,746,613

WORK HANDLING APPARATUS FOR MACHINE TOOLS INVENTOR.

WALTER R. MEYER BY :IROLD J.SIEKMANN ATTORNEYS May 22, 1956 w. R. MEYERET AL 2,746,613

woRK HANDLING APPARATUS FOR MACHINE TooLs `Filed April 22, 1953 7sheets-sheet 2 INVENTOR. WA R R. MEYER |:|G 2 `Wl-HARO J. SIEKMANN AT TOR NEYS May 22, 1956 w. R. MEYER ET AL 2,746,513

WORK HANDLING APPARATUS FOR MACHINE TOOLS Filed April 22, 1953 7Sheets-Sheet 3 F G 5 1M 'Lz-WOR.

WALTER R. MEYER HAROLD J. SIEKMANN iQ/M .2L-M

ATTORNEYS May 22, 1956 w. R. MEYER ETAL wpRK HANDLING APPARATUS FORMACHINE Toons 7 Sheets-Sheet 4 Filed April 22, 1953 INVENToR.

WALTER HAROLD J. sl 57H4@ R. MEYER EKMANN v ATTORNEYS May 22, 1956 w. R.MEYER ETAL 2,745,613

WORK HANDLING APPARATUS FOR MACHINE TOOLS Filed April 22, 1953 7Sheets-Sheet S INVENTOR. WALTER R. MEYER HAROLD J. SIEKMANN BY d t dr/ dam ATTORN EYS May 22, 1956 w. R. MEYER ETAI- WORK HANDLING APPARATUS FORMACHINE TOOLS Filed April 22, 1955 7 Sheets-Sheet 6 FIG-ll N. RRN S OEAY TYM E MEK N VME MRS. dw

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May 22, 1956 w. R. MEYER ET AL 2,746,613

WORK HANDLING APPARATUS RoR MACHINE TooLs Filed April 22, 19x55 7Sheets-Sheet '7 LI L3 7 FIG-l 2 INVENTOR. WALTER R. MEYER YHAROLD J.SIEKMANN 5W 25M/W ATTORNEYS United States Patent lO WORK HANDLINGAPPAEXTUS FOR MACHINE Walter R. Meyer and Harold J. Siekmann,Cincinnati, Ohio, assignors to The R. K. Le Blond Machine Tool Company,Cincinnati, Ohio, a corporation of Delaware Application April 22, 1953Serial No. 350,486

7 Claims. (Cl. 212-435) This invention relates to work handling andconveying devices and to methods of operation thereof, particularlydealing with such devices especially adapted for use in the loading andunloading of work members from machine tools and the like.

In the handling and conveying of work members to and from variousstations, many problems are encountered of properly engaging andsupporting the work member and holding it in the proper position when itisdelivered to a station. In particular, when work members become largeand heavy, it becomes important to have a suitable automatic mechanismfor picking up and conveying the work members in order to relieve themachine operator and similar workmen from the energy and time consuminglabor of picking up and moving the work members.

Work handling devices of this general nature, however, must berelatively compact so as not to occupy any more floor space than isabsolutely necessary, particularly Where the device is associated with amachine tool in a factory or similar location where space is costly andthe work members are probably moved only short distances from onemachine to another.

Accordingly, it will be understood that a primary object of the presentinvention is to provide an automatic work handling device and a methodof operation thereof for handling work members and conveying them to andfrom various stations.

Another object of this invention is the provision of a fully automaticpower operation work handling device for simultaneously moving andlocating work members.

Another object is the provision of a work handling device of the naturereferred to which will occupy the minimum amount of space and which willrequire a minimum amount of space in operation.

A still further object of this invention is the provision of a Workhandling device which will automatically pick up a work member in apredetermined position and convey the work member to another station anddeposit it there in a precise position.

A still further object of this invention is the provision of a workengaging and lifting element for a work handling device of the naturedescribed and an improved actuating mechanism therefor which isparticularly compact and eicient in operation.

A still further object of this invention is the provision of a memberfor engaging and picking up a work member having compound movement inspace and in which only a simple conventional motor is required foreifecting the spatial movements of the said member.

The foregoing objects and advantages of this invention become moreapparent from the following description of the drawings, in which:

Figure 1 is a front elevation of a typical center drive crankshaft latheincorporating the novel features of the work handling apparatus of thisinvention.

Figure 2 is a right hand end elevation of the center drive crankshaftlathe and loading apparatus as shown in- Figure 1.

e' ICC Figure 3 is a left hand end elevation similar to Figure 2 showingthe machine of Figure 1.

Figure 4 is a diagrammatic sectional View showing one of the loadingcranes at the beginning of a loading cycle of a work piece in the centerdrive chuck, indicated by the line 4-4 in Figure 1.

Figure 5 is a similar view of Figure 4, but showing the crankshaft aboutto be deposited in the center drive chuck.

Figure 6 is a similar view to Figure 4, but showing the position of theloading crane members at the time of deposition of the crankshaft in thecenter drive chuck.

Figure 7 is still another diagrammatic view similar to Figure 4, butshowing the crane hook removing itself from under the crankshaft andstarting in its upward stroke.

Figure 8 is a nal diagrammatic view similar to Figure 4 showing theloading crane and hook returned to starting position ready to do anunloading operation.

Figure 9 is an enlarged sectional view through one of the loading craneson the line 9-9 of Figures 2 and 10.

Figure 10 is an enlarged sectional view on the line 10-10 of Figuresland 11.

Figure 11 is an enlarged fragmentary view of the right hand loadingcrane shown in Figure 1.

Figure 12 is a diagram showing the electric and hydraulic controlcircuits and apparatus for the work handling mechanism.

For exemplary purposes this invention is shown applied to a conventionalcenter drive crankshaft line bearing turning lathe such for example asillustrated in Patent 2,191,935, issued February 27, 1940. Such a lathecomprises a base 20 upon which is mounted the center drive ring gearchuck housing 21 having the rotatable center drive work spindle 22 whichis driven by the usual main drive motor 23. Suitable tool carrier units24 and 25 are provided each side of the center drive chuck having theusual cutting tools T for operating upon the line bearings L of a workcrankshaft W, the crankshaft being supported at its ends upon centers 26carried Vin the tailstocks 27 and 28 rigidly secured to the base 20 ofthe lathe.

The center drive work spindle 22 is provided with a suitable workgripping mechanism which usually comprises a xed locating block 29 asbest shown in Figures 4 through 8 inclusive and which is located to oneside of the main axis of rotation 30 of the center drive work spindle 22and the centers 26 in the tailstocks 27 and 28. Suitable clampingmechanism is provided in the chuck in the center drive work spindle 22which is preferably operated by power clamping and unclarnping mechanismcontained in the tailstocks 27 and 25 such for example as shown inPatent 2,473,108 issued lune 14, 1949. The clamping mechanism is soorganized in the chuck body that when unclamped, there is provided anaxial passageway indicated at 31, Figures 2 and 3, through which thecrankshafts may be presented to or removed from the center drive workspindle 22 while maintained substantially on the axis 32 extendingthrough the passageway 31. The axis 32 also is arranged to pass wellover the at angularly disposed top surfaces 33 of each of the tailstocks27 and 28 of the lathe. The center drive work spindles 22 are arrangedto be stopped in accurate predetermined position to bring the accessopening 31 always to the same point 32 for the afore mentioned axialmovement of the crankshafts into and out of the center drive chucks asby means of apparatus as set forth in Patent 2,192,437 issued March 5,1940.

The basic problem solved by this invention is to provide a loadingmechanism which will take rough unmachined crankstafts which aredelivered to a loading conveyor indicated generally at 34 and to liftthem up from said conveyor to a position on the axis 32 and then to movethe rough crankshafts into the center drive chuck and deposit itdownwardly again on the axis of rotation 30 of the lathe, where theworkpiece is chucked and the cutting tools complete the machiningoperation on the line bearings L. The apparatus then is arranged toautomatically remove the crankshaft from its position on the axis 3Sagain to the position 32 and then move it axially outwardly to anunloading conveyor indicated `generally at 35. It is a further objectwhile at the same time that a crankshaft is unloaded to the unloadingconveyor that an unmachined crankshaft is loaded into the center drivechuck as described, all of the afore mentioned action being accomplishedautomatically by power controlled from a push button control stationlill conveniently located to the operator of the machine.

Referring particularly to Figures l and 2, at the right hand end of themachine there is provided a loading conveyor indicated generally at 34comprising a frame having the front legs 36 and the rear legs 37 on topof which is mounted the downwardly inclined rails 38 which slope towardthe front of the lathe and upon which are placed the rough unmachinedcrankshafts WR. Suitable curved hooked portions 39 are formed on thelower` front ends of the tracks 38 so as to position each roughcrankshaft in proper' rotary indexed position substantially on the axisof rotation 3i? of the lathe and to the right of the tailstock 28. Onthe left hand side of the lathe, as best seen in Figure 3, there isprovided the unloading conveyor indicated generally at 35 consisting ofthe front legs 40 and rear legs 41 on top of which is rigidly mountedthe rails 42 which extend downwardly to the rear of the machine androllingly support the finished crankshafts n on the end line bearings Lwhen deposited on the unloading conveyor so that they automatically rollto the rear of the machine. To keep the machine in continuous operationso far as the workpieces are concerned, it is merely necessary tocontinue to place rough workpieces WR on the rear portions of the rails38 where they slide downwardly to the front position on the axis 30 tobe received by the loading apparatus to be described. Crankshafts areautomatically received at the rear of the machine from the downwardlyinclined rails 42 from J which the finished crankshafts WF roll off anddown to the back of the lather. The operator of the lathe thus is freeto devote his entire attention to an inspection of the tools and inmeasuring the workpieces coming from the machine and at no time isrequired to physically handle the crankshafts in any manner from thebeginning to the end of the entire machining cycle.

To accomplish this desired end the loading mechanism comprises, inaddition to the loading and unloading conveyor, a transporting conveyorcomprising a pair of loading cranes indicated generally at 43 and 44each of which cranes comprises a base plate member 45 having a series ofstuds 46 upon which are journaled the spool shaped rollers 47 which rollalong on the guide surfaces 48 formed on the top and bottom edges of thechannel iron or slideway 49 which in turn is fixed by suitable screws 50to supporting bosses 51 formed rigidly with the machines structure.Suitable additional eccentrically mounted side rollers 52 carried oneccentric studs 53 on brackets 54 secured to the plates 45 and engagingthe surfaces 48 on the front of the channel 49 rovidc means for veryaccurately adjusting the rolling motion of the cranes 43 and 44 on theeye beam without loss motion or play so that the units 43 and 44 areaccurately guided on the fixed channel rail 49. The plate members 45 ofthe loading cranes 43 and 44 are rigidly connected together by means ofthe tie bars 55 which pass through the bosses 56 fixed to the plates 45and are positively held in adjustable condition in the bosses by meansof the adjusting jam nuts 57 so that both of the plates 45 of the cranemembers 43 and 44 roll along in horizontal movement in exact timedrelationship to the rigid connection of the tie bars 55. The jam nuts 57allow for relative horizontal adjustment between the two crane units forpurposes of accommodation of various types of workpieces and tooling ofthe center drive lathe to which it is applied.

On one of the crane members, such as the member 43, there is provided ahydraulic or other suitable traverse motor 55 which is securely mountedto the plate 45 of the crane 43 and has a power output shaft 59 uponwhich is fixed the rack pinion 60 which in turn engages a rack 61secured to the channel rail 49 so that upon the application of power tothe motor 53 in one direction or the other, the loading cranes 43 and 44may be traversed along the channel rail 49 to any desired position.

Each of the loading cranes 43 and 44 have depending swinging hooks whichare pivotally mounted on reciprocatable slides 62 by means of the pivotshaft 63, and which hooks terminate in suitable work engaging hookmembers 64 which in this particular exemplary embodiment are adapted toengage around the intermediate line bearing L of the crankshaft W tohold the crankshaft in desired rotary indexed position. Each of thehooks are of C-shaped construction, the loading crane 43 having a righthand C-shaped portion 65 while the left hand loading crane 44 has theoppositely directed C-shaped member 66 so that both of the hook membersmay be inserted inside of the center drive chucks through the accessopening 31 proved in the center drive chuck mechanism.

Since the apparatus for vertically reciprocating the slides 62 and forrocking the hook members 64-65 and 64-66 about their pivot shafts 63, adetailed description of one of the loading cranes, such as the crane 43,will sufiice for both. The vertically reciprocating slide 62 issupported in suitable guideways 67 in the main support housing 68 whichis securely mounted rigidly to the plate 45 by suitable bolts 69 Fixedto the slide member 62 is the bracket member 70 by suitable screws 71,upon the upper end of which bracket 70 is secured the cylinder' headblock 72 by means of a suitable tongue and keyway at 73 and the bolts74. A cylinder 75 for vertical reciprocation of the hooks is securelymounted in the cylinder member 72 and terminates in a top cylinder cap76. ln this cylinder is reciprocatably mounted the piston 77 which issecured to the piston rod '73 which projects downwardly and is connectedto a rack 79 supported in suitable guideways Sti formed on the housingmember 70. The rack 79 engages a rack pinion 81 which is fixed on thecrankshaft 82 journaled in suitable bearings 83 and 84 in the housing70.

Fixed on the crankshaft 82 between the bearings 83 and 84 is thecrankarm 85 which terminates in a crank pin 86 upon which is journaledthe connecting rod 87 which extends upwardly and is journaled on a wristpin 88 which is securely fixed to projecting bosses 89 formed integralwith the main housing member 68. Thus by reciprocation of the piston 77and rod 78 in the cylinder by appropriate application of fluid pressureto said cylinder, the rack 79 rotates the crankshaft 82 and, since theconnecting rod is rigidly held at its upper end on the wrist pin 88 thecrankshaft 82 and its main axis of rotation 90 must necessarily bereciprocated in vertical movement as best illustrated diagrammaticallyin Figures 4 through 8 inclusive.

Also fixed on the crankshaft 32 is means for simultaneously swinging thehooks about their pivot shafts 63 on the slides 62 simultaneously withand in a predetermined relationship to the vertical motion of the hooks.This apparatus comprises a disc cam 91 which is fixed on the crankshaftby a suitable key 92 and the clamp nut 93, the inner surface 94 of whichcam is provided with a specially constructed cam grove 95 in whichoperates the cam roller 96 journaled on a pin 97 carried in the outerend of the actuating lever arm 98 which in turn is rigidly fixed to thecrane hook members 65 and 66 through the medium of an adjustableconnection comprising the vabutment screws 99 carried in the hookmembers which engage an abutment stud 100 carried in a suitable boss 101of the lever arm 9S which is journaled by suitable bearing portion 102about the pivot shaft 63.

A suitable clamp bolt is provided at 103 to rigidly secure the actuatinglever 98 to the respective crane hook in the desired adjusted positionas established by the mechanism thus described. Thus with thisarrangement as the cylinder 75 actuates the rack 79 to rotate thecrankshaft and thereby vertically reciprocate the bracket 70 and slide62, the disc cam 91 is also rotated by the crankshaft in a predeterminedtimed relationship to the movement of the slide 62 so that the camgroove 95 actuating the roller 96 and the lever 98 causes the respectivehook members 65 and 66 to swing about the pivot shafts 63.

Because of the combination of the use of the rack and pinion drive79-81, the crankarm and connecting rod arrangement 85-87, and the camand lever mechanism 91-93, each of the hooks 65 and 66 followdistinctive different paths when loading and when unloading crankshaftsrelative to the chuck and the loading and unloading racks 34 and 35respectively. This is best illustrated by reference to Figures 4 to 8inclusive. In Figure 4 is is shown the loading cranes in upper positionwith the hooks located on the axis 32 for traversing the crankshaftslengthwise horizontally into and out of the center drive chucks and overor away from the loading and unloading racks. In this position thepiston rod 78 and rack 79 are fully extended downwardly relative to thecylinder 75 as the piston and rod move upwardly the crankshaft 82 isrotated clockwise and reacting against the fixed wrist pin 88 throughthe connecting rod 87 causes the slide 62 and hook to move downwardlyalong the steeply inclined path 103 from the position 32 to the position104, the rearward swinging motion to effect this combination diagonaldownward movement of the hook is caused by the appropriate shaping ofthe cam groove 95 reacting with the roller 96-on the actuating arm 98connected to the hook 65 as described. Further relative upward movementof the piston in the cylinder 75 and the changed configuration of thecam groove 95 causes the hook to move downwardly vertically from thepoint 104 to the bottom point 105 for either depositing the crankshaft Won the locating block 29 in the chuck or depositing the crankshaft onthe unloading conveyorV 35.

Continued relative upward movement of the piston in the cylinder 75together with rotation of the cam 91 causes the hook to move in anarcuate backward and upward path from the point 105 to the point 106whereupon iinal continued movement in this direction in conjunction withthe effect caused by the cam groove 95, causes the hook to move in amore horizontal sloping direction 108 upwardly to return it again to theposition 32, to thus remove the hook from position under the workpiecesbeing deposited either in the chuck or lon the unloading conveyor.

In order to remove the work from the chuck or to lift up an unfinishedworkpiece from the loading conveyor 34 the apparatus is operated in thereverse direction with the piston moving downwardly in the cylinder 75.The hook then follows a path from the position 32 diagonally rearwardlyalong the route 108 to the point 106 and then swings downwardly andforwardly in an arcuate path to the point 105 to position it under theworkpiece in the chuck or `on the load conveyor. Final continuedmovement of the apparatus back to the position shown in Figure 4, causesthe hook to first move upwardly along the path 104 and then upwardlyalong the diagonal path 103 back to the position 32. Thus there isprovided an arrangement for moving the hook in both vertical and sidemotion in a plurality of paths for both loading and unloading workrelative to the machine members.

The operation of the machine in automatic sequence may best beunderstood by reference to Figures l and 1l. Assume that the machine hascompleted the turning of the line bearings L of the crankshaft in thecenter drive chuck and has come to rest with the center drive workspindle and chuck in properly stopped indexed position as by means ofthe arrangement shown in Patent 2,192,437 cited above. The operator thenapplies the power chucking mechanism such as that shown in Patent2,473,108 cited above to unclamp the chuck, leaving the power wrenchmechanism in engagement with the chuck ready to clamp up the next roughunfinished crankshaft presented in the center drive spindle. The centers26 are then removed from the ends of the crankshaft. The operator, withthe selector switch 109, conveniently located at a suitable push buttonstation at the front of the machine, places the selector switch inautomatic position 111 so as to interconnect lead 112 with lead 113. Theoperator then presses the load push button 114 to start the automaticloading cycle. At this moment the pair of loading cranes are in the restor intermediate position as shown in Figure 1 and a limit switch LS1 iscontacted by a suitable trip dog on the member 43 so as to enable theoperator to actuate the run and jog buttons 115 of the machine forenergizing the main electrical circuit as represented by the relay coil116 to close the main contactor 117 to apply power from the lines L1, Lsand L3 to the main drive motor 23 and hydraulic system of the lathe. Assoon, however, as the loading cranes are moved to either side of theircentral rest position during the turning cycle, the limit switch LS1 isopened to block out any operation of the main drive motor of the machineso that no misoperation or accident to the machine or the operator canoccur. As soon as the load push button 114 is pressed power is appliedfrom the lead 118 to the relay coil MVR which in turn closes thecontacts 119 to thereby energize the solenoid coil N of the mainhydraulic control Valve 120 so as to apply iluid pressure from the uidpressure pump 121, which receives a supply of fluid through the suctionline 122 from the iiuid reservoir 123, to the pressure line 124, throughthe pressure reducing valve 125 and the line 126, to the pressure supplyline 127. One branch 128 of the pressure supply line 127 is permanentlyconnected into the port 129 in the bottom or piston rod chamber portionof the cylinder 75. The other branch 130 of the line 127 is connectedthrough a line 131 to the hoist control valve 132. Fluid pressure isalso connected from the line 130 through the line 133 to the line 134connected to the traverse control valve 135vand the pilot control valve136. At this time relay ULR is energized to close contacts 137 andenergized solenoid coil N of the valve 132. This connects line 138 tothe drain line 139 and blocks the pressure line 131 at the valve 132 soas to apply pressure to the piston rod end of the cylinder 75 throughthe port 140 to hold the hooks in upper position at the location 32 asdescribed. At this time limit switches LSD1 and LSDZ mounted on themember 70 are engaged by the dogs 141 carried on the rack 79 of eachcrane to hold these limit switches closed. Under these conditions relaycoil 'IRR is energized to close contacts 142 to energized solenoid coil143 of the pilot valve 136 to apply pressure through line 143 to actuatethe main traverse valve 135 to connect pressure from line 134 throughline 144 to the traverse motor 145 and to connect discharge from thismotor through the line 146 and the valve 135 to the drain line 147. Thiscauses the motor pinion 60 to be actuated to move the cranes to theright until the abutment screw 148 on the crane 43 engages the limitswitch LSA and engages the abutment surface 149 of the abutment bracket150 fixed to the rail 49. The cranes are held in contact with thesurface 149 by pressure maintained in the motor 145.

Closing of limit switch LSA energizes relay coil DUR to close contacts151 to energize solenoid coil R of the valve 132 so as to connectpressure from the line 131 to the line 13S to apply pressure on thepiston end of the- L 7 cylinder 75 to cause the hooks to move along theunloading path 108, 106, 105, 104 and 103 as seen in Figures 8 to 4inclusive. Under these conditions the left hand hook 66 picks out thefinished crankshaft from the center drive chuck while the right handhook 65 picks up a new rough crankshaft from the loading conveyor 34.

At the end of the unloading stroke, Figure 4, limit switches LSBI andLSBZ carried on the bracket member 70 are engaged by the dogs 151carried on the rack 79 which causes relay coils DCR and TLR to beenergized to close contacts 152 energizing solenoid coil S to the valve136 to connect pressure through the pilot control linc 153 to actuatethe traverse valve to apply pressure from the line 134 to the line 146and connect line 144 to the drain line la7 to cause the traverse motor145 to move the cranes to the left. This motion continues until theabutment screw 154 on the crane 44 engages the limit switch LSC and theabutment surface 155 on the abutment block 156 fixed on the left handend of the slideway 49.

When limit switch LSC is closed, pressure from line 131 is cut off atthe valve 132 while line 138 and 139 are interconnected so as to applypressure in the rod end of the cylinder 75, causing the hooks to nowfollow the loading path 103, 104, 105, 106 and 108 as shown in Figures 4to 8 and Fig. 13. Under these conditions the right hand hook 65 depositsa rough unfinished crankshaft in the center drive chuck while the lefthand hook deposits the finished crankshaft on the unloading conveyor 35,both hooks finally returning again to the upper position 32.

When the hooks reach this up position, limit switches LSDl and LSDZ areactuated by dogs 141 to cause the traverse motor 145 to move the cranesto the right. This movement continues until limit switch LSE is actuatedand opened which stops the cranes in the intermediate position shown inFigure l. When in this position, limit switch LS1 is closed by asuitable dog on one of the cranes to permit the main drive motor tooperate and tools to feed into the machine the crankshaft in the centerdrive chucks. The loading cranes remain in this intermediate position ofFigure l during the machining operations. Limit switch LSE is openedwhen the cranes move from extreme right position to extreme leftposition.

Suitable interlock mechanism for actuating the limit switch LS ofconventional design is preferably used to prevent any operation of theloading mechanism when the main drive and tool feed of the machine isoperating. Whenever the stop loader button 157 is pressed, solenoid lvlof the valve 120 is deenergized to cut off pressure from the line 126and to thus render the entire loading device inoperative.

For manual operation, the selector switch 109 is moved to manualposition to connect lead 118 with lead 158. The

load button 114 is pressed to energize solenoid N of the valve 12? toconnect pressure to the loading device. The traverse selector switch 159is then moved to right position to connect lead 160 with lead 161. Atend of travel to right, the hook selector switch 162 is moved to unloadposition to connect lead 158 to lead 163. To then traverse the cranes tothe left the traverse selector switch S is moved to left position toconnect lead 160 to lead 164. At the end of the left hand travel thehook selector switch 162 is moved to load position to connect lead 15Sto lead 165. The cranes are then moved to the right to intermediateposition of Figure l by moving the traverse selector switch to rightposition.

The cranes are stopped in intermediate position by returning thetraverse selector switch 159 to off position. The hook selector switch162 is then also turned to of position and the cycle selector switch 109is then placed in automatic position to again restore the device to theabove described automatic operation.

Having thus fully set forth and described this invention, what isclaimed as new and desired to be claimed l. In a work handling device ofthe nature described; a loading crane, a slide vertically reciprocableon said crane, a work supporting elongated hook member pivotallyconnected with the lower end of said slide and dependent therefrom, ashaft rotatable in the slide, a earn on the shaft engaging the hook sorotation of the cam will cause swinging movement of the hook on theslide, a crank on the shaft, and a connecting rod from the crank to thecrane whereby rotation of said cam will cause simultaneous reciprocationof said slide and swinging movements of said hook thereon so that thelower work engaging end of the hook follows a predetermined fixed path.

2. In a working handling device of the nature described; a loadingcrane, a slide vertically reciprocable on said crane, a work supportingelongated hook member pivotally connected with the lower end of saidslide and dependent therefrom, a shaft rotatable in the slide, a cam onthe shaft engaging the hook so rotation of the cam will cause swingingmovement of the hook on the slide, a crank on the shaft, a connectingrod from the crank to the crane whereby rotation of said cam will causesimultaneous reciprocation of said slide and swinging movements of saidhook thereon so that the lower work engaging end of the hook follows apredetermined xed path, said shaft having a pinion thereon, a rackmeshing with said pinion, and a hydraulically actuated ram connectedwith said rack for driving said cam and crank.

3. In a work handling device of the nature described; a loading crane, aslide vertically reciprocable on said crane, a work supporting elongatedhook member pivotally connected with the lower end of said slide anddependent therefrom, a shaft rotatable in the slide, a cam on the shaftengaging the hook so rotation of the cam will cause swinging movement ofthe hook on the slide, a crank on the shaft, a connecting rod from thecrank to the crane whereby rotation of said cam will cause simultaneousreciprocation of said slide and swinging movements of said hook thereonso that the lower work engaging end of the hook follows a fixedcircuitous path, said shaft having a pinion thereon, a rack meshing withsaid pinion, and a hydraulically actuated ram connected with said rackfor driving said cam and crank, said ram having two stopped endpositions so spaced that movement of the said ram therebetween willrotate said shaft one complete revolution.

4. In a work handling device of the nature described; a loading crane, aslide vertically slidable on said crane, a work supporting elongatedhook member pivoted to the lower end of said slide and dependingtherefrom, a shaft rotatable in the slide, a cam on the shaft engagingthe hook operable to swing the hook on the slide upon rotation of thecam, a crank on the shaft, a connecting rod connecting the crank withthe crane whereby rotation of said shaft will cause simultaneousreciprocation of the slide on the crane and swinging of the hook on theslide, power means for driving said shaft through one complete rotationfirst in one direction and then in the other direction, and said cambeing so constructed and arranged that the lower work engaging end ofthe hook follows a circuitous path so that in one direction of rotationof said shaft the hook will engage beneath a workpiece and lift it whilein the other direction of rotation of the shaft the hook will depositthe workpiece on a support.

5. In a work handling device of the nature described, a loading craneslidably mounted on a rail, a slide vertically slidable on said crane, awork supporting elongated hook member pivotally dependent from the lowerend of the slide and swingable thereon, a shaft rotatable on the slide,means on the shaft engaging the hook which upon rotation of said shaftcauses swinging movement of the hook, power means on said crane forsimultaneously reciprocating the slide thereon while swinging the hookon the slide whereby the lower work engaging end of the hook follows apredetermined fixed path.

6. In a work handling and transporting device of the nature described, aloading crane slidably mounted on a rail, a slide vertically slidable onsaid crane, a hook member pivoted to the lower end of said slide forswinging movement thereon, a shaft rotatable on the slide, means on theshaft engaging the hook which upon rotation of said shaft causesswinging movement of the hook, power means carried by the crane forcausing simultaneous reciprocation of the slide thereon and swingingmovement of the hook on the slide whereby the lower end of said hookfollows a circuitous path, and control means for effecting actuation ofsaid power means.

7. In a work handling and transporting device of the nature described, aloading crane slidably mounted on a rail, a slide vertically slidable onsaid crane, a hook member pivoted to the lower end of said slide forswing ing movement thereon, a shaft rotatable on the slide means on theshaft engaging the hook which upon rotation of said shaft causesswinging movement of the hook. power means carried by the crane forcausing simultaneous reciprocation of the slide thereon and swingingmovement of the hook on the slide whereby the lower end of said hookfollows a circuitous path, said power means comprising a iluid motor,means for supplying tiuid at a predetermined maximum pressure to saidmotor, and control means for eiecting actuation of said fluid motor.

References Cited in the le of this patent UNITED STATES PATENTS 891,863Ruekels June 30, 1908 1,875,730 Hively Sept. 6, 1932 2,305,868 GroeneDec. 22, 1942 2,609,108 Peterson et al Sept. 2, 1952 2,623,429 Meyer etal. Dee. 30, 1952 FOREIGN PATENTS 191,109 Germany Nov. 6, 1907

